Boost React App Performance with Lazy Loading

🪝: Our app was slow. Users were complaining. Here's the 5 things that fixed it (and the 1 thing that almost made it worse). Performance optimisation is one of those things that sounds abstract until you have actual users complaining. Here's what I've done in real projects that actually moved the needle: 1. CODE SPLITTING with React.lazy() → Don't load the whole app on first visit → Lazy load routes and heavy components → Real impact: cut initial load time by ~40% on a large project 2. MEMOISATION — but only where it matters → React.memo() for components that receive the same props often → useMemo() for expensive calculations → useCallback() for functions passed as props → WARNING: Over-memoising adds overhead. Profile first, optimise second. 3. OPTIMISED RENDER CYCLES → Identify what's causing unnecessary re-renders (React DevTools Profiler is your best friend) → Move state as close to where it's used as possible → Avoid storing derived data in state — calculate it 4. IMAGE OPTIMISATION → Lazy load images below the fold → Use appropriate formats (WebP where possible) → Set explicit width/height to avoid layout shifts 5. BUNDLE ANALYSIS → Use webpack-bundle-analyzer or Vite's rollup-plugin-visualizer → You'll be shocked what's in your bundle sometimes The thing that almost made it worse? Premature memoisation everywhere. We wrapped every component in React.memo before profiling. It actually slowed things down. MEASURE. THEN OPTIMISE. What's your go-to performance trick? #ReactJS #PerformanceOptimisation #FrontendDev #JavaScript #WebPerformance #CodeSplitting #ReactHooks

Ever wondered how apps handle scroll events, button spam, or rapid user actions efficiently? 🤔 That’s where Throttling in JavaScript comes in. 💡 Throttling ensures that a function executes at a controlled rate, no matter how many times an event is triggered. Instead of running a function hundreds of times (like during scrolling), throttling limits execution to once every fixed interval — making your app much more efficient ⚡ 📌 Why it matters: Improves performance Prevents unnecessary function calls Enhances user experience 🚀 Common use cases: Scroll events Window resizing Mouse movements API calls on frequent triggers 🧠 Key takeaway: Throttling is about limiting execution frequency, not delaying it (that’s debounce 😉). Currently exploring more performance optimization techniques to build smoother and scalable web apps. #javascript #webdevelopment #frontend #reactjs #performance #coding

𝗜 𝗰𝘂𝘁 𝗹𝗼𝗮𝗱 𝘁𝗶𝗺𝗲 𝗯𝘆 𝟰𝟬% 𝗶𝗻 𝗮 𝗥𝗲𝗮𝗰𝘁 𝗮𝗽𝗽 ⚡ No fancy tools. No rewrite. Just fundamentals. At SoftConstruct, I worked on a React.js application that grew over time 🌳. Features were added, nobody refactored, and one day we realized: this thing is slow. Noticeably slow. Management wanted a fix. Fast. Here's exactly what I did: 𝗦𝘁𝗲𝗽 𝟭: 𝗠𝗲𝗮𝘀𝘂𝗿𝗲 𝗯𝗲𝗳𝗼𝗿𝗲 𝘁𝗼𝘂𝗰𝗵𝗶𝗻𝗴 𝗮𝗻𝘆𝘁𝗵𝗶𝗻𝗴 📊 I opened Chrome DevTools, ran Lighthouse, and checked the Performance tab. The biggest problem wasn't the code logic - it was unnecessary re-renders and a massive bundle size. 𝗦𝘁𝗲𝗽 𝟮: 𝗖𝗼𝗱𝗲 𝘀𝗽𝗹𝗶𝘁𝘁𝗶𝗻𝗴 📦 We were importing everything upfront. I introduced React.lazy() and Suspense for routes that didn't need to load immediately. This alone made the initial load noticeably faster. 𝗦𝘁𝗲𝗽 𝟯: 𝗞𝗶𝗹𝗹 𝘁𝗵𝗲 𝗿𝗲-𝗿𝗲𝗻𝗱𝗲𝗿𝘀 🔁 I found components re-rendering 5-6 times on a single user action. The culprit? Inline functions and objects being passed as props, creating new references every render. I moved them out, used useCallback and useMemo where it actually mattered - not everywhere, just where profiling showed the bottleneck. 𝗦𝘁𝗲𝗽 𝟰: 𝗢𝗽𝘁𝗶𝗺𝗶𝘇𝗲 𝗶𝗺𝗮𝗴𝗲𝘀 𝗮𝗻𝗱 𝗮𝘀𝘀𝗲𝘁𝘀 🖼️ Sounds obvious. It wasn't being done. Compressed images, added lazy loading for below-the-fold content, and removed two unused libraries. 𝗦𝘁𝗲𝗽 𝟱: 𝗔𝘂𝗱𝗶𝘁 𝘁𝗵𝗲 𝗱𝗲𝗽𝗲𝗻𝗱𝗲𝗻𝗰𝗶𝗲𝘀 🧹 We had 3 date libraries. Three. I consolidated to one. Bundle dropped significantly. Result: 40% faster load times. Measured. Verified. Users noticed 🚀 The lesson? Performance optimization in React isn't about knowing clever tricks. It's about measuring, removing what's unnecessary, and being disciplined about what you add. Most slow React apps aren't slow because React is slow. They're slow because we stop paying attention. What's the biggest performance win you've achieved? Drop it below - I'm always looking for new ideas 👇 #react #performance #optimization #frontend #webdev #javascript

⚡5 React patterns that quietly make your app better: 1️⃣ Colocate state where it’s used. Global state is tempting, but local state keeps things predictable. 2️⃣ Prefer composition over configuration. Reusable components > overly flexible ones. 3️⃣ Keep side effects isolated. Cleaner logic, fewer surprises. 4️⃣ Design components for change. Today’s simple UI becomes tomorrow’s complex flow. 5️⃣ Think in data flow, not UI layers. React works best when your data structure is clear. 🚀 Great React apps aren’t built with hacks — they’re built with clear patterns and decisions. #ReactJS #ReactDevelopers #FrontendEngineering #JavaScript #ReactPatterns #WebDevelopment #FrontendDev #CodingTips

Your React App is Slow… and You Might Be the Reason Most developers use useMemo and React.memo but very few actually understand when NOT to use them ⚠️ I recently debugged a performance issue in a React dashboard. Everything looked optimized — but still, the UI was lagging. The reason? 👉 Memoization was used… but used wrongly. ⚡ Let’s break it down simply: 🔹 useMemo — Caches Calculations Use it when you have expensive computations Example: const filteredData = useMemo(() => { return data.filter(item => item.active); }, [data]); ✔ Prevents unnecessary recalculations ❌ Useless for cheap operations 🔹 React.memo — Stops Re-renders Wrap your component to avoid re-render when props don’t change const Card = React.memo(({ item }) => { return <div>{item.name}</div>; }); ✔ Great for large lists / heavy UI ❌ Useless if props change every render 🔥 The Real Problem Most people do this: Wrap everything in React.memo Add useMemo everywhere Hope performance improves 👉 Result: More complexity, same performance (sometimes worse) 💡 What Actually Works ✔ Use useMemo only for heavy calculations ✔ Use React.memo only when re-renders are costly ✔ Avoid passing new object/array references every render ✔ Measure performance before optimizing 🧠 The Mindset Shift Optimization is not about adding hooks It’s about removing unnecessary work 🚀 Final Takeaway Don’t optimize blindly. First understand: Why is it re-rendering? Is it actually slow? Then use the right tool. 👇 Curious — have you ever faced unnecessary re-renders in your app? #ReactJS #FrontendDevelopment #JavaScript #WebPerformance #ReactHooks #SoftwareEngineering #CleanCode #DevTips

Handling a single Promise is easy. Handling multiple Promises correctly is where things get interesting. In real-world apps, we often need to: • Wait for everything to complete • Pick the first successful result • React to the fastest response • Or simply collect all outcomes That’s exactly what Promise combinators solve. In my latest blog, I’ve explained: • Promise.all • Promise.any • Promise.race • Promise.allSettled Using a simple and relatable wedding planning analogy 💍 The goal was simple — make async logic feel intuitive, not intimidating. If you’ve ever been confused about these methods, this will help. Read here 👇 https://lnkd.in/gtcRWS5E Would love your feedback! #JavaScript #WebDevelopment #AsyncProgramming #Frontend

🚀 Built a To-Do List Web App — TaskFlow I recently developed TaskFlow, a To-Do List Web Application that helps users manage daily tasks efficiently with a clean and simple interface. The application allows users to add, edit, delete, and mark tasks as completed. It also includes task filtering, progress tracking, and task statistics. The most interesting part is that the app uses LocalStorage, so all tasks remain saved even after refreshing the page. 🔧 Tech Stack: • HTML • CSS • JavaScript (Vanilla JS) • LocalStorage ✨ Features: • Add, Edit, Delete Tasks • Mark Tasks as Complete • Filter Tasks (All / Pending / Done) • Progress Bar & Task Statistics • Inline Editing • Toast Notifications • Clear Completed Tasks • Data Persistence using LocalStorage 🔗 GitHub Repository: https://lnkd.in/dNTrWxBA 🔗 Live Demo: https://lnkd.in/dV59QkFY I would really appreciate any feedback or suggestions to improve this project. Thank you! #webdevelopment #javascript #frontend #project #github #Tech #developer #Fullstack #backend #Nxtwave

I deleted 70% of useEffect calls in a production React app. Nothing broke actually it became faster. The real problem wasn't "too many effects" it was derived state computed inside effects instead of during render. Context: A dashboard with filters, sorting, and real-time updates. Each filter change triggered useEffect → setState → re-render → another useEffect classical chain reaction. What I did instead: Moved all derived data into useMemo + selector functions. Used event handlers for user actions (filters, sorting). Kept useEffect only for external sync (localStorage, analytics, WebSocket). Rule I now use: If you setState inside useEffect - stop. Ask can this be calculated during render? Result: 7 effects --> 2 effects Rerenders per filter change: from 4 --> 1 Bug: impossible (no more stale closure issues) The shift in thinking: React is not reactive like Vue or Svelte. it's declarative. State --> UI. Effects are escape hatches, not data flow tools Question for you: What is the most confusing useEffect bug you've ever debugged? #react #typeScript #frontendperformance

🚀 Day 24/30 – Error Boundaries (Handle Crashes Gracefully) Everything works fine… until ONE component crashes your entire app 💥 And suddenly 👇 👉 White screen 👉 Angry users 👉 Debugging nightmare 😵 Today I learned how real-world React apps handle this ⚡ 👉 Error Boundaries --- 💻 The Problem: In React, if a component crashes ❌ 👉 The whole app can crash --- 💻 The Solution: 👉 Error Boundaries = Safety Net 🛡️ They catch errors and show fallback UI instead of breaking everything. --- 💻 Example: class ErrorBoundary extends React.Component { constructor(props) { super(props); this.state = { hasError: false }; } static getDerivedStateFromError() { return { hasError: true }; } componentDidCatch(error, info) { console.log(error, info); } render() { if (this.state.hasError) { return <h2>Something went wrong 😢</h2>; } return this.props.children; } } --- 💻 Usage: <ErrorBoundary> <Dashboard /> </ErrorBoundary>--- 🔥 What actually happens: ❌ Without Error Boundary → Whole app crashes ✅ With Error Boundary → Only broken component fails → Rest of app works smoothly --- 💡 Why this matters: - Better user experience - Prevents full app crash - Essential for production apps --- ⚡ Advanced Insight (Most people don’t know): Error Boundaries do NOT catch: ❌ API errors ❌ setTimeout errors ❌ Event handler errors 👉 You still need proper error handling there --- 🔥 Key Takeaway: Good developers fix bugs… 👉 Great developers prevent crashes --- Be honest 👇 If your app crashes today… will users see a fallback UI or a blank screen? 👀 #React #ErrorHandling #FrontendDevelopment #JavaScript #CleanCode

💡 Case Study: Improving React App Performance 🚀 Ever faced a React app that feels *painfully slow* with large data? I did. Recently, I worked on optimizing a React-based application that had noticeable lag issues. Problem: • Slow rendering with large datasets (~1000+ records) • Frequent unnecessary re-renders • Poor user experience What I did: • Used React.memo & useMemo to prevent unnecessary renders • Analyzed performance using React DevTools Profiler • Optimized API handling & state updates • Reduced redundant computations Result: • ~35–40% performance improvement • Much smoother UI interactions • Reduced rendering time significantly Key takeaway: Performance optimization is not about doing more — it's about avoiding unnecessary work. Have you faced similar performance issues in React? What worked for you? #ReactJS #PerformanceOptimization #FrontendDevelopment #JavaScript #WebDevelopment